心筋リガンド感受性K^+チャネルに対するアミオダロンの作用 Effects of amiodarone on ligand-gated K^+ channels in cardiac cells

この論文にアクセスする

この論文をさがす

著者

抄録

Amiodarone is one of the most promising antiarrhythmic drugs to reduce likelihood of sudden cardiac death. In this study effects of amiodarone on the ligand-gated K<SUP>+</SUP> channels, i.e., acetylcholine receptor-operated K<SUP>+</SUP> (KACh) channels, ATP-sensitive K<SUP>+</SUP> (KATP) channels and Na<SUP>+</SUP>-activated K<SUP>+</SUP> (KNa) channels, were examined in isolated guinea-pig atrial and ventricular myocytes by patch clamp techniques. Amiodarone in therapeutic concentrations (1-10 μM) inhibited the muscarinic acetylcholine receptor-operated K<SUP>+</SUP> current (IK.ACh) activated by extracellular application of carbachol or adenosine or by intracellular loading of GTPγS to a similar extent in atrial cells.<BR> Amiodarone in similar concentrations inhibited the activity of the KATP channels in inside-out membrane patches of ventricular cells exposed to an ATP-free solution. In a similar concentration range amiodarone also inhibited the opening of the KNa channels in inside-out membrane patches exposed to a high Na<SUP>+</SUP> (100 mM)-containing solution. Thus, these ligand-gated K<SUP>+</SUP> channels are commonly inhibited by amiodarone in the therapeutic concentrations. The inhibitory effects of amiodarone on the ligand-gated K<SUP>+</SUP> channels may play a role in the suppression of cardiac arrhythmias under pathological conditions.

収録刊行物

  • 日本薬理学雑誌

    日本薬理学雑誌 106, 77-79, 1995-09-01

    公益社団法人 日本薬理学会

参考文献:  10件中 1-10件 を表示

各種コード

ページトップへ